There is no shortage of competitive battles in UC. But there are also looming battles on the periphery. In this case, if you like to watch a good fight, get a good seat for the upcoming Google and Microsoft battle over office productivity suites.
Does moving to the cloud make sense? It could, it might, maybe even should, but that's not the reason to cloud. Businesses always care about ROI and minimizing costs. But don't look at the cloud as just a financial exercise. The goal of moving to the cloud (or not moving) should be around collaboration.
Often, the cloud begets collaboration. The cloud, in terms of cloud communications, can help an organization realize collaboration.